Hydraulic machine



Sept. 24, 1935. J. BAUMANN4 HYDRAULIC MACHINE Filed Jian. 9; 1934 2sheets-sheet 1 INVENToR JOHANNES BAUMANN BY l WZSKOQMNst-L- -ATTORNEYSept. 24, 1935. J. BAUMANN HYDRAULIC MACHINE Filed Jan. 9, 1954 2Sheets-Sheet 2 INVENTOR JOHANNES BAUMANN y BY M Q. hmm- ATTORNEYPatented Sept. 24, 17935' HYDRAULIC MACHINE JohannesA Baumann,Heidenheim-on-the-Brenz, Wurttemberg, Germany, assign'ors to J. M.Voith, Heidenheim-on-the-Brenz, Germany, a copartnership composed ofWalther Voith, Hermann Voith, and Hanns voith Application January 9,1934, Serial No. 705,857 In Germany January 10, 1933 1 Claim.

construction of hydraulic machines, such for instance as pumps,hydraulic turbines, and the like. and more particularly to improvementsin the construction of the impellers or runners of such machines.

An object of the invention is to provide an improved construction-of theimpeller or runner of a hydraulic machine of the Kaplan type havingmovable blades.

Another object of the invention is to provide an improved constructionof hydraulic machines, in which the impeller or runner blades are madeof composite material, partly of cast or forged metal and partly ofplate and structural steel.

Another object of the invention is to provide an improved hydraulicmachine of the character mentioned, in which the impeller blades arehollow.

Another object of the invention is to provide an improved light weightblade for impellers of hydraulic machines. f

Another object of the invention is to provide an improved hydraulicmachine of the charactery mentioned, which" is simple in construction,andl reliable and exact in function under all condi: tions of service.

The invention also comprises certain new vand useful improvements in theconstruction, arrangement and combination of the several parts of whichit is composed as will be hereinafter fully described and claimed. l

In the accompanying drawings:-.

Figure 1 is a view partly in section of a Kaplan type of hydraulicturbine having impeller blades lconstructed according to the presentinvention;

Fig. 2 is a vertical section of the impeller, showing the constructionof the parts within the hub thereof;

Fig. 3- is a section taken on .the une 3 3 -or Fig. 2, showing one ofthe impeller blades in plan,

a portion ofthe blade beingbroken away to show the underlying structure;and

Fig. 4 is'a section taken on the line ,4 4 of Fig. 3.

Heretofore, in the construction of impellers or runners of the Kaplantype of hydraulic ma# chines, it has been customary to form the impellerblades in one piece. The bladesvwere usually formed from cast iron, caststeel, bronze, and other suitable material. A

In the case of hydraulic machines having impellers of considerable sizeor area., it is of advantage to reduce the weight of the blades as muchas possible, so as to keep the weight of the whole machine down to aminim This invention relates to improvements in the f Furthermore, it isalso of advantage to so form v the impeller blades as to reduce' thecorrosive action on the surfaces o f the blades as much as possible.

Heretofore, by using expensive materials such 5 as cast steel andbronze, it has been possible to substantially eliminate cavitation,pitting, and corrosive action,- but it has been found that the use ofthese expensive materials has added materially to the cost of hydraulicmachines having 1o solid cast' impeller blades. Therefore, the use ofsolid cast blades is uneconomical for very large hydraulic machines.According to the present invention the impeller blades of very. largehydraulic machines can be made lighter in weight and more elcient byconstructing the blades partly of cast or forged metal and partlyofstructural and plate steel. In this way the portions or surfaces of theblades subjected to cavitation, pitting and corrosion can be formed fromexpensive material, such as cast or forged steel, while the remainingportions and surfaces of the blades can be formed from less expensivematerial, such as beams,

`girders and plate steel.

pressent invention will have less weightthan the impellers made formerlywith solid cast blades, and therefore smaller bearings can be employedfor both the impeller shafts and 'also the trun- 30 nions of theimpeller blades which are journalled in the impeller hub.

Another advantage of the present invention "is that it is possible touse suitable non-porous materials for the surfaces of the impellerblades, which materials usually are more resistant to corrosive actionthan the cast metals or mate- -rials heretofore used.

Also, by employing plate steel for forming a portion of the blades', thewarping of the blades 40 due to casting, will be eliminated, and asmoother surface requiring no finishing or polishing operations will behad. A

The preferred embodiment of the invention is shown in connection withthe well known Kaplan type of hydraulic turbine. v

Referring to the drawings and especially to Figs. 1 and 2, the turbinecomprises a casing Il which forms a peripheral water inlet in which aremounted an annular series of wicket gates or guide vanes l2, only aportion of which are shown. The lower portion I3 of the turbine casingforms an axially directed chamber in which the impeller Il operates..

The hub of the impeller I4 is iiixed the lower 1' end of a shaft I5which is joumalled in a suitable bearing I5 mounted in the turbinecasing.

Any suitable type of setting may be used for the turbine installation, aconcrete setting |1 being shown in the present instance. lThe portion ofthe setting below the turbine forms a drafttube i8 into which the wateris discharged from the impeller.

As shown, the turbine is of the adjustable blade type, and a suitablenumber of blades I9 are rotatably supported in the hub of the impellerI4 and project radially therefrom. Each blade I9 has an entrance edge 20and a discharge edge 2|, both of which edges extend from the hub of theimpeller Il outwardly to the outer edge 22 of the blade.

As shown in Figs. 2 and 3 the inner portion of each blade I9 is formedwith a trunnion 23 which is journalled in bearings 24 and 25 supportedin the hub of the impeller I4.

The trunnion 23 is formed with a collar or hub which is disposed in asuitable recess 21 in the impeller hub I4.

A suitable packing 28 is mounted in the recess 21 behind the collar orhub 26, to seal the joint between the blade and the hub of the impellerI4 and prevent the entrance of water into the interior of the impellerhub.

Means are provided for simultaneously rotating all of the blades I9 andfor maintaining them in equal angular relationship, such meanscomprising preferably an arm 30 rigidly xed on the trunnion 23 of eachbladel and links 3| which pivotally connect the arms on the differentblades to a cross head 32.

The cross head 32 is guided to reciprocate in a direction axially of theimpeller by guide pins 33, which` are mounted in the hub of the impellerin the manner shown in Fig. 2.

As shown in Figs. 1 and 2 a cap 3l is bolted or otherwise removablysecured to the lower end of the hub of the impeller Il.

The cross head 32 is bolted or otherwise fixed to the lower end of anoperating rod 35 whichv metal and structural and plate steel.

The trunnion 23, collar or hub 26 and the portions 5|, 52 and 53 of theblade can be forged from steel, or if so desired they can be cast. 'Iheportion 5| constitutes a cantilever from which the portions 52 and 53project. The entrance edge 2l is' formed on the portion 52, and thedischarge edge 2| is formed on the portion 53.

The outer peripheral edge 22 of the blade is formed on a beam 5l, whichextends from the tip of the portion 52 to the tip of the portion 53, theends of said beam being suitably joined to the tips of said portions 52and 53, by welding or in any other suitable manner. 5

Arranged in the space between the portions I, 52, 53 and 5l, arereinforcing means in the fo of a plurality of radially disposed beams 55and a plurality of clrcumferentially disposed beams 56. 'Ihese beams maybe joined together in any 10 suitable manner, such as by welding, toprovide a rigid structure.

Disposed on top of the beams 54, 55 and 55, and constituting the upperor pressure side of the blade, is a steel plate 51, and disposed on4 the1'5 lower side of said beams and constituting the non-pressure or vacuumside of the blade, is a steel plate 53.

The plates 51 and 53 may be permanently' attached in place by welding orby any other known means.

By forming the blades I9 in the above described manner, the weight ofthe blades will be materially less than the weight of similar size solidcast blades. Furthermore, the surfaces of the blades subject tocorrosion and cavitation or. pitting are formed of forged steel, whilethe balance of the blades are formed from smooth, nonporous plate steel,thereby enhancing the finish of the blades and increasing the efficiencythereof. lo

While one illustrative embodiment of the invention has been described indetail, it is not my intention to limit its scope to that embodiment orotherwise than by the terms of the appended claim. I

Having thus described my invention what I claim isz- An impellercomprising a hub. a plurality of movable blades projecting from the hub,a trunnion formed on each blade, means for journalling 40 the trunnionsin said hub, a collar formed on the outer portion of each trunnion, arecess formed in the hub for said collar, a cantilever inner portionformed on the body of each blade adjacent said collar, spaced armsprojecting outwardly 45 from the cantilever inner portion, one of saidarms constituting the entrance edge of the blade and the other armconstituting the discharge edge of the blade, a beam connecting theextremities of said arms and constituting the outer peripheral 50 edgeof each blade, a plurality of divergins radially disposed beamsextending from the inner portion of each blade outwardly to said outerperipheral edge, a plurality of substantially circumferentially arrangedbeams disposed between 55 each of said radially disposed beams andextending from the entrance edge tothe discharge edge of each blade, andplates superposed on said beams and constituting respectively thepressure and non-pressure sides of the blade. 4 00 JOHANNES BAUMANN.

